65. f4g3 Black is in zugzwang. He either has to let the king to f5 or allow the bishop to c7. 65... d8e7  66. g3c7 [%c_effect c7;square;c7;type;GreatFind;persistent;true] 66... e7c5  67. a4a5 [%c_effect a5;square;a5;type;GreatFind;persistent;true] Now White gets two passed pawns.